Cable Tester - Abnormal Termination?

[mhoppes]

I was playing around with the cable tester this evening... but can't figure out why it's giving me these results. These devices are all RocketM5s, all are operating fine... no errors on the cable and are crimped and hung standard like I crimp and hang everything else.

Thoughts?

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[lligetfa]

Describe the cable run. Are there short jumpers, patch panels, surge protectors, etc.?

I found that any of the above can skew the test.

[mhoppes]

It's a straight run right from the Netonix switch to the device.

[lligetfa]

If you unplug the rockets and retest do they pass?

[mhoppes]

It's too cold to do / try that :)

There was nothing in the instructions about powering off the devices before running the test, but I suspect having them on may contribute to something funky? I'll try turning one off later. I have a NanoBridve that tests fine while turned on though.

[mhoppes]

So power on:

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Power to device off:

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[mhoppes]

So from Chris' documentation I'm still not sure what to make of this.... it looks like it's the Rocket causing that result though:

"If the PoE device is only 10/100 capable like a Ubiquiti Rocket M5 you normally see pairs 1 and 2 reported as OK and pairs 3 and 4 report as SHORT and the pair lengths are displayed. (see below)"

So I'm not overly worried, but curious why Chris doesn't see the anomalies I'm seeing when the devices are turned on? From what I can tell, doing a cable test while the device is powered on will result in all kinds of strange results and probably shouldn't be done to reliably determine much.

[sirhc]

When I run this on my Rockets in service on towers I get the results below:

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We use the T568B Standard shown below:

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I would bet your cables are crimped wrong, they have to be as I can run this on over 100 radios in service on 8 different switches and it is always the same.

[lligetfa]

I had similar results when a device was connected. I think the best test procedure would be to test the cable before a device is connected.

When I pressed Chris on it, the answer I got was they didn't write the code, and that I was unfair to compare it to a Fluke tester that costs thousands.

Basically, I was just concerned about managing expectations.

[sirhc]

It is true the test routine is a function of the switch core itself and we just write code that asks it to be run the real meat and potatoes are already written in the switch.

It is not as accurate as a real tester just like airVIEW is not as accurate as a real spectrum analyzer but it is a nice little tool to use.

But Matt s results tell me his cable is punched down/crimped "wrong"